20402026440 has 64 divisors (see below), whose sum is σ = 62860311360. Its totient is φ = 5293497600.

The previous prime is 20402026439. The next prime is 20402026453. The reversal of 20402026440 is 4462020402.

It is a Harshad number since it is a multiple of its sum of digits (24).

It is a self number, because there is not a number n which added to its sum of digits gives 20402026440.

It is an unprimeable number.

It is a polite number, since it can be written in 15 ways as a sum of consecutive naturals, for example, 2293086 + ... + 2301965.

It is an arithmetic number, because the mean of its divisors is an integer number (982192365).

Almost surely, 2^20402026440 is an apocalyptic number.

20402026440 is a gapful number since it is divisible by the number (20) formed by its first and last digit.

It is an amenable number.

20402026440 is an abundant number, since it is smaller than the sum of its proper divisors (42458284920).

It is a pseudoperfect number, because it is the sum of a subset of its proper divisors.

20402026440 is a wasteful number, since it uses less digits than its factorization.

20402026440 is an evil number, because the sum of its binary digits is even.

The sum of its prime factors is 4595102 (or 4595098 counting only the distinct ones).

The product of its (nonzero) digits is 3072, while the sum is 24.

Adding to 20402026440 its reverse (4462020402), we get a palindrome (24864046842).

The spelling of 20402026440 in words is "twenty billion, four hundred two million, twenty-six thousand, four hundred forty".